[Mac] Refactor the fullscreen toolbar animation

chrome/browser/ui/cocoa/fullscreen_toolbar_controller.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h"
 
 #include <algorithm>
 
-#import "base/auto_reset.h"
 #include "base/command_line.h"
 #import "base/mac/mac_util.h"
 #include "base/mac/sdk_forward_declarations.h"
 #import "chrome/browser/ui/cocoa/browser_window_controller.h"
 #import "chrome/browser/ui/cocoa/fullscreen/fullscreen_menubar_tracker.h"
+#import "chrome/browser/ui/cocoa/fullscreen/fullscreen_toolbar_animation_controller.h"
 #include "chrome/common/chrome_switches.h"
-#import "third_party/google_toolbox_for_mac/src/AppKit/GTMNSAnimation+Duration.h"
 #include "ui/base/cocoa/appkit_utils.h"
 #import "ui/base/cocoa/nsview_additions.h"
 #import "ui/base/cocoa/tracking_area.h"
 
 namespace {
 
-// The duration of the toolbar show/hide animation.
-const NSTimeInterval kDropdownAnimationDuration = 0.20;
-
-// If the fullscreen toolbar is hidden, it is difficult for the user to see
-// changes in the tabstrip. As a result, if a tab is inserted or the current
-// tab switched to a new one, the toolbar must animate in and out to display
-// the tabstrip changes to the user. The animation drops down the toolbar and
-// then wait for 0.75 seconds before it hides the toolbar.
-const NSTimeInterval kTabStripChangesDelay = 0.75;
-
 // Additional height threshold added at the toolbar's bottom. This is to mimic
 // threshold the mouse position needs to be at before the menubar automatically
 // hides.
 const CGFloat kTrackingAreaAdditionalThreshold = 20;
 
 // Visibility fractions for the menubar and toolbar.
 const CGFloat kHideFraction = 0.0;
 const CGFloat kShowFraction = 1.0;
 
 // The amount by which the toolbar is offset downwards (to avoid the menu)
 // when the toolbar style is OMNIBOX_TABS_HIDDEN. (We can't use
 // |-[NSMenu menuBarHeight]| since it returns 0 when the menu bar is hidden.)
 const CGFloat kToolbarVerticalOffset = 22;
 
 }  // end namespace
 
-// Helper class to manage animations for the dropdown bar.  Calls
-// [FullscreenToolbarController changeToolbarFraction] once per
-// animation step.
-@interface DropdownAnimation : NSAnimation {
- @private
-  FullscreenToolbarController* controller_;
-  CGFloat startFraction_;
-  CGFloat endFraction_;
-  CGFloat toolbarFraction_;
-}
-
-@property(readonly, nonatomic) CGFloat endFraction;
-@property(readonly, nonatomic) CGFloat toolbarFraction;
-
-// Designated initializer.  Asks |controller| for the current shown fraction, so
-// if the bar is already partially shown or partially hidden, the animation
-// duration may be less than |fullDuration|.
-- (id)initWithFraction:(CGFloat)fromFraction
-          fullDuration:(CGFloat)fullDuration
-        animationCurve:(NSAnimationCurve)animationCurve
-            controller:(FullscreenToolbarController*)controller;
-
-@end
-
-@implementation DropdownAnimation
-
-@synthesize endFraction = endFraction_;
-@synthesize toolbarFraction = toolbarFraction_;
-
-- (id)initWithFraction:(CGFloat)toFraction
-          fullDuration:(CGFloat)fullDuration
-        animationCurve:(NSAnimationCurve)animationCurve
-            controller:(FullscreenToolbarController*)controller {
-  // Calculate the effective duration, based on the current shown fraction.
-  DCHECK(controller);
-  CGFloat fromFraction = [controller toolbarFraction];
-  CGFloat effectiveDuration = fabs(fullDuration * (fromFraction - toFraction));
-
-  if ((self = [super gtm_initWithDuration:effectiveDuration
-                                eventMask:NSLeftMouseDownMask
-                           animationCurve:animationCurve])) {
-    startFraction_ = fromFraction;
-    endFraction_ = toFraction;
-    controller_ = controller;
-  }
-  return self;
-}
-
-// Called once per animation step.  Overridden to change the floating bar's
-// position based on the animation's progress.
-- (void)setCurrentProgress:(NSAnimationProgress)progress {
-  toolbarFraction_ =
-      startFraction_ + (progress * (endFraction_ - startFraction_));
-  [controller_ updateToolbar];
-}
-
-@end
-
 @interface FullscreenToolbarController (PrivateMethods)
 
 // Updates the visibility of the menu bar and the dock.
 - (void)updateMenuBarAndDockVisibility;
 
 // Methods to set up or remove the tracking area.
 - (void)updateTrackingArea;
 - (void)removeTrackingAreaIfNecessary;
 
 // Returns YES if the mouse is inside the tracking area.
 - (BOOL)mouseInsideTrackingArea;
 
 // Whether the current screen is expected to have a menu bar, regardless of
 // current visibility of the menu bar.
 - (BOOL)doesScreenHaveMenuBar;
 
 // Returns YES if the window is on the primary screen.
 - (BOOL)isWindowOnPrimaryScreen;
 
 // Returns |kFullScreenModeHideAll| when the overlay is hidden and
 // |kFullScreenModeHideDock| when the overlay is shown.
 - (base::mac::FullScreenMode)desiredSystemFullscreenMode;
 
-// Animate the overlay to the given visibility with animation. If |visible|
-// is true, animate the toolbar to a fraction of 1.0. Otherwise it's 0.0.
-- (void)animateToolbarVisibility:(BOOL)visible;
-
-// Cancels the timer for hiding the floating bar.
-- (void)cancelHideTimer;
-
-// Methods called when the hide timers fire. Do not call directly.
-- (void)hideTimerFire:(NSTimer*)timer;
-
 // Stops any running animations, etc.
 - (void)cleanup;
 
 // Whether the menu bar should be shown in immersive fullscreen for the screen
 // that contains the window.
 - (BOOL)shouldShowMenubarInImmersiveFullscreen;
 
 @end
 
 @implementation FullscreenToolbarController
 
 @synthesize slidingStyle = slidingStyle_;
 
 - (id)initWithBrowserController:(BrowserWindowController*)controller
                           style:(FullscreenSlidingStyle)style {
   if ((self = [super init])) {
     browserController_ = controller;
     systemFullscreenMode_ = base::mac::kFullScreenModeNormal;
     slidingStyle_ = style;
+    animationController_.reset(new FullscreenToolbarAnimationController(self));
   }
 
   return self;
 }
 
 - (void)dealloc {
   DCHECK(!inFullscreenMode_);
   [super dealloc];
 }
 
@@ skipping 38 matching lines @@
 }
 
 - (void)windowDidBecomeMain:(NSNotification*)notification {
   [self updateMenuBarAndDockVisibility];
 }
 
 - (void)windowDidResignMain:(NSNotification*)notification {
   [self updateMenuBarAndDockVisibility];
 }
 
-- (void)lockBarVisibilityWithAnimation:(BOOL)animate {
-  base::AutoReset<BOOL> autoReset(&isLockingBarVisibility_, YES);
-  [self ensureOverlayShownWithAnimation:animate];
-}
-
-- (void)releaseBarVisibilityWithAnimation:(BOOL)animate {
-  base::AutoReset<BOOL> autoReset(&isReleasingBarVisibility_, YES);
-  [self ensureOverlayHiddenWithAnimation:animate];
-}
-
 - (void)ensureOverlayShownWithAnimation:(BOOL)animate {
-  if (!inFullscreenMode_)
-    return;
-
-  if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kKioskMode))
-    return;
-
-  if (self.slidingStyle != FullscreenSlidingStyle::OMNIBOX_TABS_HIDDEN)
-    return;
-
-  [self cancelHideTimer];
-  [self animateToolbarVisibility:YES];
+  animationController_->AnimateToolbarIn();
 }
 
 - (void)ensureOverlayHiddenWithAnimation:(BOOL)animate {
-  if (!inFullscreenMode_)
-    return;
-
-  if (self.slidingStyle != FullscreenSlidingStyle::OMNIBOX_TABS_HIDDEN)
-    return;
-
-  if ([browserController_ isBarVisibilityLockedForOwner:nil])
-    return;
-
-  if ([self mouseInsideTrackingArea] ||
-      [menubarTracker_ state] == FullscreenMenubarState::SHOWN) {
-    return;
-  }
-
-  [self cancelHideTimer];
-  [self animateToolbarVisibility:NO];
+  animationController_->AnimateToolbarOutIfPossible();
 }
 
+// Cancels any running animation and timers.
 - (void)cancelAnimationAndTimer {
-  [self cancelHideTimer];
-  [currentAnimation_ stopAnimation];
-  currentAnimation_.reset();
+  animationController_->StopAnimationAndTimer();
 }
 
 - (void)revealToolbarForTabStripChanges {
   if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kEnableFullscreenToolbarReveal)) {
     return;
   }
 
-  // Reveal the toolbar for tabstrip changes if the toolbar is hidden.
-  if (ui::IsCGFloatEqual([self toolbarFraction], kHideFraction)) {
-    isRevealingToolbarForTabStripChanges_ = YES;
-    [self ensureOverlayShownWithAnimation:YES];
-  }
+  animationController_->AnimateToolbarForTabstripChanges();
 }
 
 - (void)setSystemFullscreenModeTo:(base::mac::FullScreenMode)mode {
   if (mode == systemFullscreenMode_)
     return;
   if (systemFullscreenMode_ == base::mac::kFullScreenModeNormal)
     base::mac::RequestFullScreen(mode);
   else if (mode == base::mac::kFullScreenModeNormal)
     base::mac::ReleaseFullScreen(systemFullscreenMode_);
   else
     base::mac::SwitchFullScreenModes(systemFullscreenMode_, mode);
   systemFullscreenMode_ = mode;
 }
 
 - (void)mouseEntered:(NSEvent*)event {
   // Empty implementation. Required for CrTrackingArea.
 }
 
 - (void)mouseExited:(NSEvent*)event {
   DCHECK(inFullscreenMode_);
   DCHECK_EQ([event trackingArea], trackingArea_.get());
 
   if ([browserController_ isBarVisibilityLockedForOwner:nil])
     return;
 
   // If the menubar is gone, animate the toolbar out.
-  if ([menubarTracker_ state] == FullscreenMenubarState::HIDDEN) {
-    base::AutoReset<BOOL> autoReset(&shouldAnimateToolbarOut_, YES);
+  if ([menubarTracker_ state] == FullscreenMenubarState::HIDDEN)
     [self ensureOverlayHiddenWithAnimation:YES];
-  }
 
   [self removeTrackingAreaIfNecessary];
 }
 
 - (void)updateToolbar {
   [browserController_ layoutSubviews];
   [self updateTrackingArea];
+  animationController_->UpdateToolbar();
 
   // In AppKit fullscreen, moving the mouse to the top of the screen toggles
   // menu visibility. Replicate the same effect for immersive fullscreen.
   if ([browserController_ isInImmersiveFullscreen])
     [self updateMenuBarAndDockVisibility];
 }
 
 - (BrowserWindowController*)browserWindowController {
   return browserController_;
 }
@@ skipping 22 matching lines @@
 - (CGFloat)toolbarFraction {
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kKioskMode))
     return kHideFraction;
 
   switch (slidingStyle_) {
     case FullscreenSlidingStyle::OMNIBOX_TABS_PRESENT:
       return kShowFraction;
     case FullscreenSlidingStyle::OMNIBOX_TABS_NONE:
       return kHideFraction;
     case FullscreenSlidingStyle::OMNIBOX_TABS_HIDDEN:
-      FullscreenMenubarState menubarState = [menubarTracker_ state];
-      if (menubarState == FullscreenMenubarState::SHOWN)
-        return kShowFraction;
+      if ([self mustShowFullscreenToolbar])
+        return 1.0;

[erikchen, 2016/10/21 20:39:28]

probably kShowFraction?

 
-      if ([self mouseInsideTrackingArea])
-        return kShowFraction;
-
-      if (currentAnimation_.get())
-        return [currentAnimation_ toolbarFraction];
-
-      if (isLockingBarVisibility_)
-        return kHideFraction;
-      else if (isReleasingBarVisibility_)
-        return kShowFraction;
-      else if ([browserController_ isBarVisibilityLockedForOwner:nil])
-        return kShowFraction;
-
-      if (hideTimer_.get() || shouldAnimateToolbarOut_)
-        return kShowFraction;
+      if (animationController_->IsAnimationRunning())
+        return animationController_->GetToolbarFractionFromProgress();
 
       return [menubarTracker_ menubarFraction];
   }
 }
 
+- (BOOL)mustShowFullscreenToolbar {
+  if (!inFullscreenMode_)
+    return NO;
+
+  if (slidingStyle_ == FullscreenSlidingStyle::OMNIBOX_TABS_PRESENT)
+    return YES;
+
+  if (slidingStyle_ == FullscreenSlidingStyle::OMNIBOX_TABS_NONE)

[erikchen, 2016/10/21 19:36:59]

Don't we want toolbarFraction to return kHideFraction? Ditto for the other
places that return NO.

[spqchan, 2016/10/21 20:34:18]

I'm confused on what you're getting at.

[erikchen, 2016/10/21 20:39:28]

Oh, I see what happened. The slidingStyle_ conditionals are duplicated here and
in lines 232-235. Semantically, the checks here make sense, but it's the
conditionals in lines 232-235 that actually cause kShowFraction and
kHideFraction to be returned.

+    return NO;
+
+  FullscreenMenubarState menubarState = [menubarTracker_ state];
+  return menubarState == FullscreenMenubarState::SHOWN ||
+         [self mouseInsideTrackingArea] ||
+         [browserController_ isBarVisibilityLockedForOwner:nil];
+}
+
 - (BOOL)isFullscreenTransitionInProgress {
   return [browserController_ isFullscreenTransitionInProgress];
 }
 
 - (BOOL)isInFullscreen {
   return inFullscreenMode_;
 }
 
 - (BOOL)isMouseOnScreen {
   return NSMouseInRect([NSEvent mouseLocation],
                        [[browserController_ window] screen].frame, false);
 }
 
 - (void)setTrackingAreaFromOverlayFrame:(NSRect)frame {
   NSRect contentBounds = [contentView_ bounds];
   trackingAreaFrame_ = frame;
   trackingAreaFrame_.origin.y -= kTrackingAreaAdditionalThreshold;
   trackingAreaFrame_.size.height =
       NSMaxY(contentBounds) - trackingAreaFrame_.origin.y;
 }
 
-- (void)animationDidStop:(NSAnimation*)animation {
-  if (isRevealingToolbarForTabStripChanges_) {
-    if ([self toolbarFraction] > 0.0) {
-      // Set the timer to hide the toolbar.
-      [hideTimer_ invalidate];
-      hideTimer_.reset(
-          [[NSTimer scheduledTimerWithTimeInterval:kTabStripChangesDelay
-                                            target:self
-                                          selector:@selector(hideTimerFire:)
-                                          userInfo:nil
-                                           repeats:NO] retain]);
-    } else {
-      isRevealingToolbarForTabStripChanges_ = NO;
-    }
-  }
-
-  // Reset the |currentAnimation_| pointer now that the animation is over.
-  currentAnimation_.reset();
-}
-
-- (void)animationDidEnd:(NSAnimation*)animation {
-  [self animationDidStop:animation];
-  [self updateTrackingArea];
-}
-
 @end
 
 @implementation FullscreenToolbarController (PrivateMethods)
 
 - (void)updateMenuBarAndDockVisibility {
   if (![self isMouseOnScreen] ||
       ![browserController_ isInImmersiveFullscreen]) {
     [self setSystemFullscreenModeTo:base::mac::kFullScreenModeNormal];
     return;
   }
@@ skipping 66 matching lines @@
   NSScreen* primaryScreen = [[NSScreen screens] firstObject];
   return (screen == primaryScreen);
 }
 
 - (base::mac::FullScreenMode)desiredSystemFullscreenMode {
   if ([self shouldShowMenubarInImmersiveFullscreen])
     return base::mac::kFullScreenModeHideDock;
   return base::mac::kFullScreenModeHideAll;
 }
 
-- (void)animateToolbarVisibility:(BOOL)visible {
-  CGFloat fraction = visible ? kShowFraction : kHideFraction;
-
-  // If we're already animating to the given fraction, then there's nothing
-  // more to do.
-  if (currentAnimation_ && [currentAnimation_ endFraction] == fraction)
-    return;
-
-  // In all other cases, we want to cancel any running animation (which may be
-  // to show or to hide).
-  [currentAnimation_ stopAnimation];
-
-  // Create the animation and set it up.
-  currentAnimation_.reset([[DropdownAnimation alloc]
-      initWithFraction:fraction
-          fullDuration:kDropdownAnimationDuration
-        animationCurve:NSAnimationEaseOut
-            controller:self]);
-  DCHECK(currentAnimation_);
-  [currentAnimation_ setAnimationBlockingMode:NSAnimationNonblocking];
-  [currentAnimation_ setDelegate:self];
-
-  // If there is an existing tracking area, remove it. We do not track mouse
-  // movements during animations (see class comment in the header file).
-  [self removeTrackingAreaIfNecessary];
-
-  [currentAnimation_ startAnimation];
-}
-
-- (void)cancelHideTimer {
-  [hideTimer_ invalidate];
-  hideTimer_.reset();
-}
-
-- (void)hideTimerFire:(NSTimer*)timer {
-  DCHECK_EQ(hideTimer_, timer);  // This better be our hide timer.
-  [hideTimer_ invalidate];       // Make sure it doesn't repeat.
-  hideTimer_.reset();            // And get rid of it.
-  base::AutoReset<BOOL> autoReset(&shouldAnimateToolbarOut_, YES);
-  [self animateToolbarVisibility:NO];
-}
-
 - (void)cleanup {
-  [self cancelAnimationAndTimer];
+  animationController_->StopAnimationAndTimer();
   [[NSNotificationCenter defaultCenter] removeObserver:self];
 
   [self removeTrackingAreaIfNecessary];
 
   // Call the main status resignation code to perform the associated cleanup,
   // since we will no longer be receiving actual status resignation
   // notifications.
   [self setSystemFullscreenModeTo:base::mac::kFullScreenModeNormal];
 
   menubarTracker_.reset();
 
   // No more calls back up to the BWC.
   browserController_ = nil;
 }
 
 - (BOOL)shouldShowMenubarInImmersiveFullscreen {
   return [self doesScreenHaveMenuBar] && [self toolbarFraction] > 0.99;
 }
 
 @end